Job searching is spread across five different tools that don’t talk to each other. So I made one that does. It’s called HeffOS. The piece that surprised people most is the AI interview prep tool. Most interview prep is just reading questions off a screen. But the part that actually trips you up is saying your answers out loud, which I never practiced enough and it showed. So I built a voice interview simulator instead. The AI interviewer asks questions out loud. You answer by speaking, not typing. Then it shows you what was weak about your answer and a stronger version to learn from. You can set the difficulty and the interview stage, so a recruiter screen and a final round feel like genuinely different conversations. I designed it end to end and built it into a real working app with Claude Code. Voice and all. Full Case Study Here